This invention relates to bonding apparatus of the type employed in vacuum bagging, and, more particularly, to a seal around the perimeter of such apparatus.
Vacuum bag assemblies are used in making laminated products in which laminates are adhesively secured together. Vacuum bag assemblies are also used for effecting repairs such as on airplane components made of synthetics and laminates with or without metal, such as for example graphite fibers or sheets that are bonded into a unitary monolith by resin polymers, adhesives and other synthetic materials. Thus, where a flaw or fissure has developed in a laminate component, it may be repaired employing a vacuum bag assembly.
Examplary vacuum bag assemblies, such as disclosed in U.S. Pat. No. 4,287,015, typically comprise a air-tight base plate on which the laminations with their applied adhesives are placed. Next, an air-tight upstanding ribbing structure is affixed to the air-tight base plate and well spaced inwardly from the perimeter of air-tight base plate to surround the laminations with their applied adhesives. A stretchable air-tight vacuum bag membrane is laid cross the laminations with their applied adhesives and is extended beyond the laminations to completely contact the ribbing structure and to be held securely at selected locations along the perimeter of the air-tight base plate, while being stretched into continuous firm air sealing contact with the air-tight upstanding ribbing structure. Fastening means are usually employed to secure the stretchable air-tight vacuum bag membrane to the air-tight base plate along selected portions of the perimeter. Finally, a vacuum means is secured in part to the vacuum bag assembly, whereby a vacuum may be drawn within the vacuum volume determined by the air-tight base, the continuous air-tight upstanding ribbing structure and the stretchable air-tight vacuum bag membrane.
A problem with many conventional vacuum bagging systems is the recurring labor and material costs and the high degree of operator skill required. A reusable vacuum bag would minimize the recurring labor and material costs resulting in high quality bonding and it would only require minimal operator skill.